Wez Furlong has posted an example showing a cool little tool that he's whipped up that looks to bridge the gap between PHP and the Objective-C runtime:

I've had some code hanging around on my laptop for the better part of a year (feels like two, but I don't think I've had my MBP that long), that implements a bridge between PHP and the Objective-C runtime.

Yesterday I debugged the last portion that I regarded as a total showstopper for anyone else that might want to use it, and added a script that pulls in your PHP installation and dependent libraries (such as Fink or Mac Ports libraries) and generates a "Bundle" and optionally a DMG containing the Bundle.

He had a fellow developer try it out on Leopard too (things broke, but most are fixed) who also created a simple ping example to show off this project in its (very early) alpha stages. He mentions in the post how to get to the code, but if you can't locate it, just wait a bit - he'll have it posted up soon enough.